| Summary: | 碩士 === 國立中央大學 === 光電科學研究所 === 93 === In this thesis, the physical phenomenon and characteristics of GaN light emitting diode (LED) with different Micron-Size active region were fabricated and analyzed. Devices design and the optoelectronic characteristics will be discussed.
For the devices design, we combine both photo lithography and ion implantation technique to fabricate various disk diameters (3, 5, 7.5, 10, 15, 20 μm) LEDs. The ion implantation technique was used for defined non-radiation region and confined the transport current. However, various micron-size LEDs was successfully fabricated using these two techniques and better current injection than KSU paper discussed at the same Voltage.
For the optoelectronic characteristics analysis, the disk diameter dependent blue shift of electro-luminescence (EL) spectra were observed. The smaller size 3µm LED resulted in bigger blue shift 87.5meV than 20µm 52.9meV under current density in range 200 to 15915 (A/cm2) this disk diameter dependent effect might be due to the competition between junction temperature and balanced quantum confined Stark effect (QCSD). The power density of LEDs radiation was measured by Integration Sphere and surface. The luminous intensity seems independent on the active dimension of micron-size LEDs. Our device 10μm size Quantum efficiency (Q.E.) is better than the S.X.Jin best device (12μm) Q.E. and array device 9μm Q.E. .This breakthrough might be contributed to the micron-size current confinement of Mg ion implanted.
|
|---|
